Control for a Powered Surgical Instrument

ABSTRACT

A surgical instrument is provided for cutting bone and other tissue. The instrument includes a housing. A plurality of sensors is located in the housing in a spaced apart orientation from each other. A collar is moveably mounted to the housing into a plurality of different collar orientations on the housing. A lever comprising an actuator is moveably coupled to the collar and, with the collar located in any one of the plurality of different collar orientations, the lever is operable to move the actuator relative to one of the plurality of sensors in order to vary a signal produced by that sensor.

PRIORITY

The present application is a continuation of, and claims priority toU.S. patent application Ser. No. 12/052,549, (allowed) filed Mar. 20,2008, which is incorporated herein by reference.

FIELD OF THE INVENTION

The present disclosure generally relates to surgical instruments and inparticular to surgical instruments for dissecting bone and other tissue.

BACKGROUND

Surgical instruments may use a variety of methods to control theoperating speed of the instrument. For example, a powered surgicalinstrument used for dissecting bone or tissue may use a control leverthat may be moved to increase or decrease the operating speed of theinstrument.

Difficulties may arise in the control of the powered surgicalinstrument. Some conventional powered surgical instruments include thecontrol lever fixed to the instrument. The control lever may beresiliently and pivotally coupled to the instrument such that a user maypivot the control lever towards the instrument to increase the operatingspeed, and then allow the control lever to resiliently pivot away fromthe instrument to decrease the operating speed. However, in somesituations, the control lever may be interfered with by, for example,angled cutting attachments that are coupled to and powered by thepowered surgical instrument, wires, pins, fixtures, and a variety ofother obstructions known in the art. In addition, the fixed position ofthe control lever may result in wrist and/or hand fatigue to the user.

Therefore, what is needed is an improved control for a surgicalinstrument.

SUMMARY

The present disclosure provides many technological advances that can beused, either alone or in combination, to provide an improved control fora powered surgical instrument and/or an improved system and method forcontrolling powered surgical instruments.

In one embodiment, a surgical instrument includes a housing, a pluralityof sensors located in the housing in a spaced apart orientation fromeach other, a collar moveably mounted to the housing into a plurality ofdifferent collar orientations on the housing; and a lever comprising anactuator and moveably coupled to the collar, wherein, with the collarlocated in any one of the plurality of different collar orientations,the lever is operable to move the actuator relative to one of theplurality of sensors in order to vary a signal produced by that sensor.

Further forms and embodiments will become apparent from the detaileddescription provided hereinafter. It should be understood that thedetailed description and specific examples, while indicating preferredembodiments, are intended for purposes of illustration only and are notintended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 a is an environmental view illustrating an embodiment of asurgical instrument for the dissection of bone and other tissueaccording to the teachings of an embodiment of the present disclosureoperatively associated with a patient undergoing a craniotomy procedure.

FIG. 1 b is a perspective view illustrating an embodiment of thesurgical instrument of FIG. 1 a.

FIG. 1 c is a perspective, cross sectional view illustrating anembodiment of the surgical instrument of FIG. 1 a.

FIG. 1 d is a perspective, cross sectional view illustrating anembodiment of the surgical instrument of FIG. 1 a.

FIG. 2 a is a perspective view illustrating an embodiment of a backnutused with the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 2 b is a cross sectional view illustrating an embodiment of thebacknut of FIG. 2 a.

FIG. 3 a is a rear perspective view illustrating an embodiment of aconnector insert used with the surgical instrument of FIGS. 1 a, 1 b, 1c, and 1 d.

FIG. 3 b is a front perspective view illustrating an embodiment of theconnector insert of FIG. 3 a.

FIG. 3 c is a cross sectional view illustrating an embodiment of theconnector insert of FIGS. 3 a and 3 b.

FIG. 4 is a perspective view illustrating an embodiment of a sensor ringused with the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 5 is a perspective view illustrating an embodiment of a board usedwith the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 6 is a bottom view illustrating an embodiment of a sensor used withthe surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 7 is a perspective view illustrating an embodiment of a collar usedwith the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 8 a is a perspective view illustrating an embodiment of a pressring used with the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 8 b is a rear view illustrating an embodiment of the press ring ofFIG. 8 a.

FIG. 9 a is a perspective view illustrating an embodiment of a leverused with the surgical instrument of FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 9 b is a cross sectional view illustrating an embodiment of thelever of FIG. 9 a.

FIG. 10 a is a perspective view illustrating an embodiment of anactuator holder used with the surgical instrument of FIGS. 1 a, 1 b, 1c, and 1 d.

FIG. 10 b is a cross sectional view illustrating an embodiment of theactuator holder of FIG. 10 .

FIG. 10 c is a perspective view illustrating an embodiment of anengagement member used with the surgical instrument of FIGS. 1 a, 1 b, 1c, and 1 d.

FIG. 10 d is a cross sectional view illustrating an embodiment of theengagement member of FIG. 10 c.

FIG. 11 a is a flow chart illustrating an embodiment of a method forcontrolling a surgical instrument.

FIG. 11 b is a cross sectional view illustrating an embodiment of thelever pivoted towards the housing on the surgical instrument with thecollar in a first collar orientation.

FIG. 11 c is a perspective, cross sectional view illustrating anembodiment of the lever pivoted towards the housing on the surgicalinstrument.

FIG. 11 d is a cross sectional view illustrating an embodiment of thelever pivoted towards the housing on the surgical instrument with thecollar in a second collar orientation.

FIG. 11 e is a cross sectional view illustrating an embodiment of theswitch on the surgical instrument moved into a second switchorientation.

FIG. 11 f is a cross sectional view illustrating an embodiment of theswitch on the surgical instrument moved into a second switch orientationwith the lever pivoted towards the housing.

FIG. 11 g is a perspective view illustrating an embodiment of the distalend of the lever extended.

FIG. 11 h is a perspective, cross sectional view illustrating anembodiment of the distal end of the lever extended.

DETAILED DESCRIPTION

The present disclosure relates to surgical tools, and more particularly,to a control for use in powered surgical instruments. It is understood,however, that the following disclosure provides many differentembodiments, or examples, for implementing different features of thecontrol. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. In addition, the presentdisclosure may repeat reference numerals and/or letters in the variousexamples. This repetition is for the purpose of simplicity and clarityand does not in itself dictate a relationship between the variousembodiments and/or configurations discussed.

Referring initially to FIG. 1 a, a surgical instrument for thedissection of bone and other tissue constructed in accordance with theteachings of a first preferred embodiment of the present disclosure isillustrated and generally identified at reference numeral 100. Thesurgical instrument 100 is shown operatively associated with a patient Xfor performing a craniotomy. It will become apparent to those skilled inthe art that the subject invention is not limited to any particularsurgical application but has utility for various applications in whichit is desired to dissect bone or other tissue.

With reference to FIGS. 1 b, 1 c, and 1 d, the surgical instrument 100is illustrated to include a generally cylindrical housing 102 having anouter surface 102 a, an inner surface 102 b, and defining a housingvolume 102 c. A motor (not illustrated for clarity) may be housed in thehousing volume 102 c and may include a plurality of motor components. Acoupling 103 couples a surgical attachment 104 to the housing 102. Inthe preferred embodiment, the surgical attachment 104 includes a cuttingtool or dissection tool 104 a, illustrated in FIG. 1 b, that is coupledto the motor located in the housing volume 102 c, although the type oftool is not essential to implementing the present invention. A distalend of the cutting tool 104 a includes an element adapted for aparticular procedure, such as a cutting element. The surgical attachment104 may provide a gripping surface for use by a surgeon and may alsoshield underlying portions of the surgical instrument 100 during asurgical procedure. A plurality of components of a control for thesurgical instrument 102 is coupled to the housing 102 and will bedescribed in further detail below. The control components include abacknut 200, a connector insert 300, a sensor ring 400, a board 500, aplurality of sensors 600, a collar 700, a press ring 800, a lever 900,and a switch 1000.

Referring now to FIGS. 1 b, 1 c, 1 d, 2 a, and 2 b, the backnut 200 isillustrated. The backnut 200 includes a generally cylindrical base 202having an outer surface 202 a, an inner surface 202 b, and an endwall202 c having an inner surface 202 d and an outer surface 202 e oppositethe inner surface 202 d. A backnut volume 204 is defined by the base 202between the inner surface 202 b and the inner surface 202 d of endwall202 c and includes a backnut volume entrance 206 located opposite thebase 202 from the endwall 202 c. A backnut member 208 extends from theouter surface 202 e of the endwall 202 c on the base 202, includes adistal end 208 a and defines a passageway 210 extending from the distalend 208 a to the backnut volume 204. The backnut 200 is located in thehousing volume 102 c of the housing 102 such that the outer surface 202a of the backnut 202 engages the inner surface 102 b of the housing 102and the backnut member 208 extends out of the housing, as illustrated inFIGS. 1 c and 1 d.

Referring now to FIGS. 1 b, 1 c, 1 d, 3 a, 3 b, and 3 c, the connectorinsert 300 is illustrated. The connector insert 300 includes a generallycircular base 302 having a front surface 302 a, a rear surface 302 b,and an outer surface 302 c extending between the front surface 302 a andthe rear surface 302 b. A plurality of apertures 304 extend into thebase 302 from the front surface 302 a. A plurality of apertures 306extend into the base 302 from the rear surface 302 b. A passageway 308extends through the base 302 from the front surface 302 a to the rearsurface 302 b. The connector insert 300 is located in the housing volume102 of the housing 102 such that the outer surface 302 c of theconnector insert 300 engages the inner surface 102 b of the housing 102and the front surface 302 a of the connector insert 300 extends into thebacknut volume 204 through the backnut volume entrance 206, asillustrated in FIGS. 1 c and 1 d.

Referring now to FIGS. 1 b, 1 c, 1 d, 2 b, and 4, the sensor ring 400 isillustrated. The sensor ring 400 includes a generally cylindrical base402 having a front surface 402 a, a rear surface 402 b, and an outersurface 402 c extending between the front surface 402 a and the rearsurface 402 b. A passageway 402 d is defined by the base 402 and extendsthrough the base 402 from the front surface 402 a to the rear surface402 b. A plurality of sensor channels 404 are defined by the base 402and located in a spaced apart orientation on the outer surface 402 c ofthe base 402. In an embodiment, each of the sensor channels 404 aresubstantially similar and include a sensor mounting channel 404 aextending into the base 402 from the outer surface 402 c and a pluralityof lead channels 404 b extending from the sensor mounting channel 404 ato the front surface 402 a of the base 402. In the illustratedembodiment, the sensor channels 404 are radially spaced apart from eachother on the base 402 by approximately 90 degrees. However, the sensorchannels 404 may be more or less in number, and may be spaced furtherapart or closer together at regular or irregular intervals. The sensorring 400 is located in the backnut volume 204 adjacent the backnutvolume entrance 206 and the front surface 302 a of the connector insert300 with the outer surface 402 c of the sensor ring 400 engaging theinner surface 202 b of the backnut 200, as illustrated in FIGS. 1 c and1 d.

Referring now to FIGS. 1 b, 1 c, 1 d, 2 b, 4, and 5, the board 500 isillustrated. The board 500 includes a generally circular base 502 havinga front surface 502 a, a rear surface 502 b, and an outer surface 502 cextending between the front surface 502 a and the rear surface 502 b. Apassageway 502 d extends through the base 502 a from the front surface502 a to the rear surface 502 b. In an embodiment, the board 500 may bea printed circuit board and may include circuitry and/or circuit boardcomponents known in the art. The board 500 is located in the backnutvolume 204 such that the rear surface 502 b of the board 500 engages thefront surface 402 a of the sensor ring 400, as illustrated in FIGS. 1 cand 1 d.

Referring now to FIGS. 1 b, 1 c, 1 d, 2 b, 4, 5, and 6, one of theplurality of sensors 600 is illustrated. The sensor 600 includes asensor member 602 having a front surface 602 a, a rear surface 602 b,and a bottom surface 602 c extending between the front surface 602 andthe rear surface 602 b. A plurality of sensor leads 604 extend from thefront surface 602 a of the sensor member 602. In an embodiment, thesensor 600 is an A132x Ratiometric Linear Hall-Effect

Sensor for High-Temperature Operation, available commercially fromAllegro MicroSystems, Inc. 115 Northeast Cutoff, Worcester, Mass.01615-0036. A sensor 600 is positioned in each of the sensor channels404 such that the sensor member 602 is located in the sensor mountingchannel 404 a and the sensor leads 604 extend through the lead channels404 b and into engagement with the outer surface 502 c and/or circuitrycomponents of the board 500, as illustrated in FIGS. 1 c and 1 d. In anembodiment, the sensor leads 604 are coupled to circuitry on the board500. With the sensors 600 positioned in the sensor channels 404, thesensors are located adjacent the inner surface 202 b of the backnut 200and the inner surface 102 b of the housing 102 and are radially spacedapart from each other by approximately 90 degrees, as illustrated inFIGS. 1 c and 1 d.

Referring now to FIGS. 1 b, 1 c, 1 d, 2 b, and 7, the collar 700 isillustrated. The collar 700 includes a generally cylindrical base 702having a front surface 702 a, a rear surface 702 b, an outer surface 702c extending between the front surface 702 a and the rear surface 702 b,and an inner surface 702 d located opposite the outer surface 702 c andextending between the front surface 702 a and the rear surface 702 b. Apassageway 702 e extends through the base 702 from the front surface 702a to the rear surface 702 b. The collar 700 includes an axis 702 fcentrally located in the passageway 702 c. A plurality of lever mountingmembers 704 extend from the outer surface of the base 702 adjacent therear surface 702 b in a spaced apart orientation from each other suchthat they define a channel 706 between them. Each of the lever mountingmembers 704 define a mounting aperture 704 a. The collar 700 is mountedto the outer surface 102 a of the housing 102 adjacent the backnut 200,as illustrated in FIGS. 1 c, and 1 d, such that the collar 700 is ableto rotate about the housing 102 and the axis 702 f, as will be describedin further detail below.

Referring now to FIGS. 1 b, 1 c, 1 d, 7, 8 a, and 8 b, the press ring800 is illustrated. The press ring 800 includes a generally cylindricalbase 802 having a front surface 802 a, a rear surface 802 b locatedopposite the front surface 802 a, an outer surface 802 c extendingbetween the front surface 802 a and the rear surface 802 b, and an innersurface 802 d located opposite the outer surface 802 c and extendingbetween the front surface 802 a and the rear surface 802 b. A passageway802 e extends through the base 802 from the front surface 802 a to therear surface 802 b. In an embodiment, the press ring 800 is taperedtowards the front surface 802 a and includes a plurality of channels 804defined along the front surface 802 a and into the base 802. A pluralityof indents 806 are defined by the base 802 in a radially spaced apartorientation, with each indent extending from the outer surface 802 c tothe rear surface 802 b of the base 802. In an embodiment, the indents806 are radially spaced apart at approximately 90 degree intervals. Thepress ring 800 is press fit to the outer surface 102 a of the housing102 between the housing 102 and the collar 700 such that the housing 102is located in the passageway 802 e defined by the press ring 800 withthe inner surface 802 d of the press ring 800 engaging the outer surface102 a of the housing 102, as illustrated in FIGS. 1 c and 1 d. With thepress ring 800 press fit to the housing 102, the collar 700 is free torotate about the housing 102 but may not be removed from the housing 102without the use of a tool to remove the press ring 800. In anembodiment, the collar 700 includes features (not illustrated) that mayengage the indents 806 on the press ring 800 in order to provide aplurality of different, discrete orientations in which, due to theengagement of those features and the indents 806, rotation of the collar700 relative to the housing 102 is resisted.

Referring now to FIGS. 1 b, 1 c, 1 d, 7, 9 a, and 9 b, the lever 900 isillustrated. The lever 900 includes an elongated base 902 having a topwall 902 a and a pair of opposing side walls 902 b and 902 c extendingfrom opposing sides of the top wall 902 a. The top wall 902 a and thesides walls 902 b and 902 c terminate at an end 902 d. A collar mountingmember 904 extends from an end of the base 902 opposite the end 902 dand defines a collar housing 904 a and a plurality of mounting apertures906. The base 902 also includes a switch mounting region 908 thatincludes a switch mounting volume 910 defined between the top wall 902 aand the side walls 902 b and 902 c and a switch mounting aperture 912extending through the top wall 902 a to the switch mounting region 910.An extendable distal end mounting volume 914 is also defined between thetop wall 902 a and the sides walls 902 b and 902 c and is locatedbetween the switch mounting volume 910 and the end 902 d of the base902. The lever 900 is pivotally coupled to the collar 700 by, forexample, a rod extending through the mounting apertures 906 defined bythe collar mounting member 904 on the lever 900 and the mountingapertures 704 a defined by the lever mounting members 704 on the collar700, as illustrated in FIGS. 1 c and 1 d. A resilient member 916 islocated in the channel 706 defined by the lever mounting members 704 andengages the lever 900 and the collar 700 to resiliently bias the lever900 away from the outer surface 102 a of the housing 102, as illustratedin FIG. 1 b and 1 c. A distal end 918 includes a slidable coupling 920,illustrated in FIG. 1 c, that is located in the extendable distal endmounting volume 914 and slidably coupled to the lever 900.

Referring now to FIGS. 1 b, 1 c, 1 d, 9 a, 9 b, 10 a, 10 b, 10 c, and 10d, the switch 1000 is illustrated. The switch 1000 includes an actuatorholder 1002 that includes a base 1004 having a top surface 1004 a, abottom surface 1004 b located opposite the top surface 1004 a, a frontsurface 1004 c extending between the top surface 1004 a and the bottomsurface 1004 b, a rear surface 1004 d located opposite the front surface1004 c and extending between the top surface 1004 a and the bottomsurface 1004 b, and a pair of opposing side surfaces 1004 e and 1004 fextending between the top surface 1004 a , the bottom surface 1004 b,the front surface 1004 c, and the rear surface 1004 d. An actuatorhousing 1006 is defined by the base 1004, extends into the base 1004from the top surface 1004 a, and is located adjacent the rear surface1004 d. A fastener passageway 1008 is defined by the base 1004 andextends through the base 1004 from the top surface 1004 a to the bottomsurface 1004 b. The switch 1000 also includes an engagement member 1010that includes a base 1012 having a top surface 1012 a, a bottom surface1012 b located opposite the top surface 1012 a, a front surface 1012 cextending between the top surface 1012 a and the bottom surface 1012 b,a rear surface 1012 d located opposite the front surface 1012 c andextending between the top surface 1012 a and the bottom surface 1012 b,and a pair of opposing side surfaces 1012 e and 1012 f extending betweenthe top surface 1012 a , the bottom surface 1012 b, the front surface1012 c, and the rear surface 1012 d. A guide member 1014 extends fromthe bottom surface 1012 b of the base 1012, and the guide member 1014and the base 1012 define a fastener aperture 1016 extending through theguide member 1014 and into the base 1012. In the illustrated embodiment,the fastener aperture 1016 is threaded. An actuator 1018, illustrated inFIGS. 1 c and 1 d, may be positioned in the actuator holder 1006. In anembodiment, the actuator 1018 may be, for example, a magnet, a samariumcobalt magnet, and/or a variety of other actuators known in the art. Theswitch 1000 is moveably coupled to the lever 900 by positioning theactuator holder 1002 in the switch mounting volume 910 and positioningthe engagement member 1010 adjacent the top wall 902 a of the lever 900such that the guide member 1014 on the engagement member 1010 extendsthrough the switch mounting aperture 912 defined by the lever 900. Afastener 1020 is then positioned in the fastener passageway 1008 definedby the actuator holder 1002 and engaged with the fastener aperture 1016defined by the engagement member 1010 to coupled the switch 1000 to thelever 900. With the switch 1000 coupled to the lever 900, the switch1000 may slidingly move relative to the lever 900 in the switch mountingaperture 912.

Referring now to FIGS. 1 b, 1 c, 1 d, 11 a, 11 b, and 11 c, a method1100 for controlling a surgical instrument is illustrated. The method1100 begins at block 1102 where the surgical instrument 100 is provided.In an embodiment, the collar 700 on the surgical instrument 100 ispositioned in an orientation A such that the actuator 1018 in the switch1000 on the lever 900 is aligned with one of the sensors 600,illustrated in FIG. 1 c, with the resilient member 916 biasing the lever900 and the actuator 1018 away from the housing 102 and the sensor 600,respectively. The method 1100 then proceeds to block 1104 where thelever 900 is pivoted to produce a signal from one of the sensors 600. Auser of the surgical instrument 100 may apply a force to the lever 900to move the lever in a direction B, illustrated in FIG. 1 c, such thatthe actuator 1018 is moved towards the sensor 600. In an embodiment, thesensor 600 is a Hall-effect sensor and the actuator 1018 is a magnet,and the movement of the actuator 1018 relative to the sensor 600 willvary a signal produced by the sensor 600. For example, as the magnetactuator 600 is moved towards the Hall-effect sensor 600, theHall-effect sensor 600 will detect the gauss field strength of themagnet actuator 600 and provide a variable voltage signal which is readby control circuitry and used to increase the motor speed and the speedof the cutting tool 104 a. With the lever 900 fully pivoted such thatthe lever 900 is immediately adjacent the housing 102 and the actuator1018 is adjacent the sensor 600, as illustrated in FIGS. 1 d, 11 c, and11 b, the signal sent from the sensor 600 will result in the motorsupplying the maximum amount of speed allowed to the cutting tool 104 a.In an embodiment, when the user of the surgical instrument 100 releasesthe lever 900, the resilient member 916 will resiliently bias the lever900 and the actuator 1018 away from the housing 102 and the sensor 600,respectively, which will vary the signal that is produced by theHall-effect sensor 600 and sent to the motor (not shown) to decrease thespeed of the motor and the speed of the cutting tool 104 a.

Referring now to FIGS. 1 b, 1 c, 1 d, 11 a, 11 b, and 11 c, the method1100 proceeds to blocks 1106 and 1108 where the collar 700 is rotatedand the lever 900 is pivoted to produce a signal from a different sensor600 than the sensor 600 that produced the signal in block 1104 of themethod 1100. As described above, in an embodiment, the collar 700 ismoveably coupled to the housing 102 such that the collar 700 may rotateabout the housing 102 into a plurality of different, discreteorientations. In the illustrated embodiment, a crest-to-crest wavespring 1106 a provides tension to keep the collar 700 and the press ring800 engaged. To rotate the collar 700, the collar 700 is pulled orpushed along the length of the housing 102 and away from the press ring800 to disengage the collar 700 from the press ring 800, rotated (e.g.by 90 degrees), and then released to allow the tension from thecrest-to-crest wave spring 1106 a to re-engage the collar 700 and thepress ring 800. As such, the collar 700 may be rotated about the housing102 into an orientation C such that the actuator 1018 in the switch 1000on the lever 900 is aligned with one of the sensors 600 and may be movedrelative to the sensor 600 to produce a signal from that sensor 600, asillustrated in FIG. 11 d. In an embodiment, the collar 700 may berotated about the housing 102 into any orientation corresponding to asensor 600 in order to allow the lever 900 to be pivoted to vary themotor speed and the speed of the cutting tool 104 a. Thus, a surgicalinstrument 100 is provided that includes a lever and actuator that maybe moved about the housing of the surgical instrument 100 to avoidobstructions or to ease user fatigue.

Referring now to FIGS. 1 b, 1 c, 1 d, 11 a, 11 e and 11 f, the method1100 proceeds to block 1110 where the switch 1000 is moved to preventsignal production. With the collar 700 in any orientation correspondingto a sensor 600 such as, for example, the orientation A illustrated inFIG. 1 c, the switch 1000 may be moved in a direction D from a firstswitch orientation E, illustrated in FIG. 1 c, to a second switchorientation F, illustrated in FIG. 11 e, where the actuator 1018 hasbeen translated along the length of the lever 900. When the lever 900 isthen pivoted, as described above with reference to block 1104 of themethod 1100, the actuator 1018 will not be located adjacent the sensor600, as illustrated in FIG. 11 f, and the signal from the sensor 600will not be varied such that the motor will not vary the speed of thecutting tool 104 a.

Referring now to FIGS. 1 b, 1 c, 1 d, 11 a, 11 g, and 11 h, the method1100 proceeds to block 1112 where the distal end 918 on the lever 900 isextended. The slidable coupling 920 allows the distal end 918 to beextended from the lever 900 to effectively increase the length of thelever 900, as illustrated in FIGS. 11 g and 11 h.

While the invention has been particularly shown and described withreference to the preferred embodiment thereof, it will be understood bythose skilled in the art that various changes in form and detail may bemade therein without departing from the spirit and scope of theinvention. Furthermore, the housings and/or components may be replacedby other suitable elements to achieve similar results. In addition, avariety of materials may be used to form the various components and therelative sizes of components may be varied. Therefore, the claims shouldbe interpreted in a broad manner, consistent with the present invention.

1-20. (canceled)
 21. A control for a powered surgical instrument, thecontrol comprising: a housing; a plurality of sensors located in thehousing in a spaced apart orientation from each other; and a leverpivotal relative to the housing and moveable about the housing into aplurality of different radial orientations, wherein each of theplurality of different radial orientations corresponds to a respectiveone of the plurality of sensors, the lever comprising an actuatorwherein, with the lever located in any one of the plurality of differentradial orientations, the lever is operable to move the actuator relativeto the respective one of the plurality of sensors in order to vary asignal that is produced by that sensor due to the relative movement ofthe actuator.
 22. The control of claim 21, wherein the plurality ofsensors are located adjacent an inner surface of the housing in aradially spaced apart orientation from each other.
 23. The control ofclaim 22, wherein the plurality of sensors are radially spaced apart byapproximately 90 degrees.
 24. The control of claim 21, furthercomprising a collar rotatably attached to the housing and operable to beindexed into the plurality of different collar orientations, the leverbeing carried on the collar.
 25. The control of claim 24, wherein thelever is resiliently and pivotally coupled to the collar.
 26. Thecontrol of claim 21, further comprising: a switch moveably coupled tothe lever, wherein the actuator is located on the switch.
 27. Thecontrol of claim 26, wherein the switch comprises a first switchorientation on the lever in which movement of the lever relative to oneof the plurality of sensors varies a signal produced by that sensor, anda second switch orientation on the lever in which movement of the leverrelative to one of the plurality of sensors does not vary a signalproduced by that sensor.
 28. The control of claim 21, furthercomprising: a distal end on the lever, wherein the distal end isextendable from the lever to increase the length of the lever.
 29. Apowered surgical instrument, comprising: a housing; a motor housed inthe housing; at least one sensor disposed in the housing and configuredto generate a signal to increase and decrease the operating speed of themotor; and a lever pivotally connected to the housing and comprising aswitch and an actuator, the switch being configured to displace theactuator along the lever from a first orientation on the lever in whichmovement of the lever relative to the at least one sensor varies asignal produced by the at least one sensor, and a second orientation onthe lever in which movement of the lever relative to the at least onesensor does not vary a signal produced by the at least one sensor. 30.The instrument of claim 29, wherein said at least one sensor comprises aplurality of sensors coupled to the motor and housed in the housing in aspaced apart orientation from each other, the lever being disposable ina plurality of different orientations that respectively align withdifferent sensors of the plurality of sensors.
 31. The instrument ofclaim 29, further comprising a collar mounted to and rotatable about thehousing into a plurality of discrete collar orientations, and whereineach discrete collar orientation corresponds to a respective one of theplurality of sensors, wherein the lever is carried on the collar in amanner that aligns the actuator with a different respective sensor ofthe plurality of sensors for each of the plurality of discrete collarorientations.
 32. The instrument of claim 29, wherein the plurality ofsensors are located adjacent an inner surface of the housing in aradially spaced apart orientation from each other.
 33. The instrument ofclaim 32, wherein the plurality of sensors are radially spaced apart byapproximately 90 degrees.
 34. The instrument of claim 29, wherein theactuator is disposed adjacent a proximal end of the switch.
 35. Theinstrument of claim 29, further comprising: a distal end on the lever,wherein the distal end is extendable from the lever.
 36. A method forcontrolling a surgical instrument, the method comprising: providing asurgical instrument comprising a housing and a lever pivotably androtatably associated with the housing, the lever comprising an actuator,wherein the lever is located in a first radial orientation relative tothe housing, and wherein the first radial orientation corresponds to afirst sensor in the housing; pivoting the lever to move the actuatorrelative to the first sensor in order to vary a signal that is producedthe first sensor due to the relative movement of the actuator; rotatingthe lever into a second radial orientation on the housing, wherein thesecond radial orientation corresponds to a second sensor in the housing;and pivoting the lever to move the actuator relative to the secondsensor in order to vary a signal that is produced by the second sensordue to the relative movement of the actuator.
 37. The method of claim36, further comprising: extending a distal end of the lever.
 38. Themethod of claim 36, wherein the lever is connected to a collar rotatableabout the housing, and wherein rotating the lever comprises rotating thecollar away from a position where the lever is aligned with the firstsensor and into a position where the lever is aligned with the secondsensor.
 39. The method of claim 36, wherein the varying of signalsproduced by the first sensor and the second sensor result in the varyingof the speed of a cutting tool that is coupled to the housing.
 40. Themethod of claim 36, further comprising: moving a switch that includesthe actuator and that is coupled to the lever, wherein the moving of theswitch prevents the varying of a signal produced by the first sensor orthe second sensor when the actuator is moved relative to that sensor.